What level describes the differences in pigment levels in the wing cells of butterflies with different alleles?

• A. Molecular
• B. Cellular
• C. Behavioral
• D. Population

Answer: (B)

The differences in pigment levels in the wing cells of butterflies with different alleles are best described at the cellular level. This is because the expression of alleles directly affects the cells within the butterfly's wings, leading to variations in pigmentation that can be observed at that cellular location. Here, the alleles contribute to the biochemical pathways that determine pigment production.

At the molecular level, one might focus on the specific genes and their sequences or the proteins that these genes encode. However, the question targets the manifestation of those genetic differences, which occurs at the cellular level. Similarly, behavioral and population levels pertain to the actions and interactions of butterflies or the traits observed in groups rather than the direct cellular differences in pigmentation resulting from genetic variation. Therefore, focusing on the cellular aspect allows for a clear understanding of how genetic differences translate into observable traits.